Leading-in wire for electric devices



' Pa tented Apr. 4, 1939 PATENT OFFICE LEADING-IN FOB ELECTRIC DEVICESMarcello Pirani, Berlin-Wilmersdorf, and Ham Wolfl', Zeuthen, Germany,'aulgnors to General Electric Company, a corporation of New York NoDrawing. Application December 14, 1983, Se-

gigsls No. 702,425. In Germany January 6. 3 Claims. (Cl. 49-92) a r.

Our invention relates to leading-in wires for fined to amounts underflve per cent of the total electric devices comprising a glass bulb orenalloy. I v closure and more particularly to a new composi- Thefollowing suitable compositions may be tion for leading-in wires sealedin a bulb of used for the new leading-in wire alloy:

5 boron-silicate glass which has a higher melting p t by point than theusual lead and calcium glasses. weight Our new leading-in wire isparticularly adapt- (1) Tungsten g .able for electric discharge tubescomprising a Nickel 12 bulb oi boron-silicate glass containing less thanComm 4 1 50 per cent of silicic acid and more than 30 per nu cent ofboric acid with a small amount of alkali. (2) Tungsten 74 The bulbs ofsuch tubes attain a temperature Nickel -7...- 22 of several hundreddegrees centlgrade during Cobalt 4 operation and contain a filling of avapor of substances such as sodium, cadmium, magnesium or thallium. P

An object of our invention therefore is to provide a leading-in wirewhich will form a reliable seal with a hard glass such as boron-silicate20 glass.

According to our invention the new leading-in wire consists of an alloyof tungsten and nickel to which-is preferably added a small amountofcobalt. The proportions are preferably 70-85 per cent of tungsten and15-30 per cent of nickel. Preferably a small part of the nickel, up to 5per cent of the total quantity of alloy, is replaced by cobalt. Thisalloy can be readily drawn into wire. The sealing in the glass isimproved by the an addition of the cobalt while the drawing qualitiesare not noticeably impaired by it when'con- What we claim as new anddesire to secure by Letters Patent ofthe United States is:

1. As a new article of manufacture, a leadingin wire consisting of analloy oftungsten and nickel, said alloy having a coeillcient andexpansion adapting it to be sealed to hard glass.

2. As a new article of manufacture, a leadingin wire consisting of an.alloy of seventy to eighty-five per cent of, tungsten and fifteen tothirty per cent of nickel.

'3. As a, new article of manufacture, a boron silicate glass articlehaving seal ed therein a leading-in wire consisting of an alloy oftungsten and nickel.

MARCELLO PIRANI. HANS WOLFE.

CERTIFICATE OF CORRECTION. Patent No. 2,153,390. April 1;, 1959.

MARCELLO PIRANI, E'I" AL,

It is hereby certified that error appears in the printed specificationof the above numbered patent requiring correction as follows: Secondcolumn, line 18, claim 1, for "and" read of; and that the said LettersPatent should be read with this correction therein that the some mayconform to the rec- 0rd of the case in "the Pater 1t Office,

Signed and sealedthis 25rd day of May, AB'D 1959 Henry Ve n Arsdele(Seal) Acting Commissioner of Petenteu

